内置式永磁同步电机转子初始位置估计方法

针对无位置传感器永磁同步电机控制系统起动运行困难的问题,提出一种基于混合信号注入的内置式永磁同步电机改进转子磁极初始位置估计方法.采用注入高频旋转电压信号的方法检测磁极位置,设计一种通过PI跟踪观测器对所构建磁极位置误差信号进行控制的方案,当误差调节至零时将获得磁极位置初判值,降低了算法的复杂性.以磁极位置初判值为矢量角,往定子绕组注入2个方向相反的脉冲电压矢量,通过比较直轴电流大小可以简单、有效地判断出磁极极性,实现对位置初判值进行校正,从而获得转子初始位置估计值.应用所提出的估计方法对一台22kW内置式永磁同步电机进行实验,得到转子位置电角度平均估计误差为4.6°.     

内嵌式永磁同步电机转子初始位置检测(英文)

针对内置式永磁同步电机的无感器运行问题,提出一种转子初始位置估计方法。通过对内嵌式永磁同步电机的定子绕组施加合适的电压脉冲,检测未通电相的端电压就可以获得转子的位置信息。利用磁饱和效应对凸极性的影响来区分南北极,从而区别2个稳定区,转子初始位置估计方法的分辨率为30°电角度。以DSP控制的永磁同步电机系统为试验平台,对所提出的方法进行了试验验证及试验结果分析,结果表明,提出的方法能够可靠而有效的估计初始转子位置。     

Effects of rotor bar and end-ring faults over the signals of a position estimation strategy for induction motors

The effect of rotor faults, such as broken bars and end-rings, over the signals of a position estimation strategy for induction motor drives is analyzed using a multiple coupled circuit model. The objective of this analysis is to establish the possibility of using the estimation strategy signals for fault diagnosis in variable-speed electric drives. This strategy is based on the effect produced by inductance variation on the zero-sequence voltage, when exciting the motor with a predefined inverter switching pattern. Experimental results illustrate the feasibility of the proposal.     

Initial rotor position estimation of an interior permanent-magnet synchronous machine using carrier-frequency injection methods

This work presents a method using carrier-frequency injection to estimate the initial rotor position and magnetic polarity for an interior permanent-magnet synchronous machine. A nonsaturating inductance model of the machine provides no information about the polarity of the rotor magnet because the position observer based on this model is locally stable at both poles. To distinguish the polarity of the rotor magnet, the magnetic saturation effect can be used. The Taylor series can be used to describe the nonlinear magnetic saturation relationship between the current and the flux linkage in the d-axis rotor reference frame. The second-order term produces the second harmonic component of the carrier frequency, and the sign of its coefficient identifies the polarity of the rotor magnet being tracked. Both simulation and experimental results show good response of the position observer at several rotor electrical positions using either a rotating vector in the stationary reference frame or a oscillating vector in the estimated rotor reference frame.     

Initial rotor position estimation of interior permanent magnet synchronous motor using optimal voltage vector

The initial rotor position estimation is a serious problem affecting sensorless drives of permanent magnet synchronous motors. This paper presents an estimation method of initial rotor position for interior permanent magnet synchronous motors. The principle of the estimation is based on the nonlinear magnetization characteristics of the stator core caused by the magnet of the rotor. The estimation is performed using the variation of the current response caused by the magnetic saturation when the voltage vector is applied to the motor. This method can be performed without motor parameters and any additional hardware. Decision method of the optimal voltage vector applied to the motor is also proposed to accurately implement the estimation. Experimental results show that the initial rotor position can be estimated without rotating the rotor by using the optimal voltage vector. It is found that the average of the estimation error is ±1.34 electrical degrees, and the estimation is completed within 15.2 ms in the test motor. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 156(4): 69–76, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20062     

A periodic burst injection method for deriving rotor position insaturated cage-salient induction motors without a shaft encoder

This paper describes a new method for estimating the incremental rotor position for an induction machine without using a shaft sensor. The method assumes a saturated induction motor having an engineered cage saliency spanning one pole pitch. The voltage-source inverter driving the machine is also used to inject a high-frequency signal which is needed to detect position. The paper discusses two ways in which this can be achieved. This method has been proven successful with a loaded machine at low speeds and overcomes problems associated with saturation     

一种新型无刷直流电机转子位置检测方法

提出一种新的基于假中性点电压交流分量积分过零点的转子位置检测方法。通过对假中性点电压信号特性的分析,提出假中性点电压交流分量积分过零点对应电机换相时刻。该方法低速检测范围更宽,实现简单,不要求无刷直流电机具有理想的梯形波磁场,在直流母线电压低的中小功率应用场合尤其具有技术优势。实验验证了方法的有效性。     

Sensorless rotor position estimation at standstill of cylindrical brushless dc motors using opened phase voltage change caused by eddy currents

A rotor position estimation of a cylindrical brushless dc motor at standstill has been difficult to obtain. Therefore, torque control of a motor has been difficult at starting of the motor, and realization of the position estimation at standstill has been sought. This paper proposes a simple processing of a rotor for which nonmagnetic materials are pasted on the rotor surface. This processing generates an eddy current on nonmagnetic materials and causes an opened phase voltage change according to rotor position. The experimental results using a microcomputer show that it is possible to estimate rotor position of the cylindrical motor despite a standstill by using the opened phase voltage change. ©�1998 Scripta Technica, Electr Eng Jpn, 126(1): 52–60, 1999     

永磁同步电机转子磁位自检测复合方法

针对永磁同步电机转子磁位和速度检测问题,提出了将脉振高频电压信号注入法和模型参考自适应法有机结合的新型无速度传感器的复合方法,建立了无传感器矢量控制系统.通过设计速度切换器,实现了两种方法间的平滑切换.解决了单一方法不能在全速度范围内同时兼顾良好的动态、稳态性能的问题,使系统实现了包括初始磁位在内的转子位置和速度的精确检测和控制.仿真结果表明,该复合方法能可靠的实现永磁同步电机全速度范围内的起动和运行.系统具有优良的动态、稳态性能.     

Sensorless initial rotor position estimation of surface permanent-magnet synchronous motor

This paper presents a method of estimating the initial rotor position of a surface permanent-magnet synchronous motor without a position sensor. The estimation is performed by using the nonlinear magnetization characteristics of the stator core caused by the magnet of the rotor. This method is based on the principle that the d-axis current value for the voltage vector applied to the motor under some conditions increases as the voltage vector generated from the inverter approaches the N pole of the rotor. During the estimation process, the rotor is practically at standstill. The experimental results show that the average of the estimation error is /spl plusmn/3.8 electrical degrees.     

PM motors for direct driving optical telescope

This article details the task of developing the drive systems for VLT (Very Large Telescope) control. The project entails the realization and the coordinated operation of four 8 m diameter optical telescopes in Chile for the period 1995-1998. A direct drive system has been chosen as the optimal drive solution from a performance standpoint. It consists of a segmental dual axial air gap brushless motor which is an unusually large torque motor, which must be manufactured piecewise and assembled on-site. Furthermore, the torque motor must couple in the stiffest possible way to the relatively light telescope assembly, and the thermal perturbations to the environment must be minimized. Finally, in spite of their very large size, the torque motors must be controlled with a very high control bandwidth; the torque slew rate must be extremely steep. The authors describe the design of the drive system including motor torque ripple. Finite element analysis of the motor is also discussed     

一种检测无刷直流电机转子位置的新方法

针对传统的无刷直流电机无位置传感器检测转子位置信号需要多级模拟滤波器、复杂的相移电路以及与霍尔传感器输出的信号不一致的缺陷,本文提出了一种通过对三相端电压进行简单滤波、比较后直接获得转子位置信号的新方法.实验结果表明:新方法无需相移,检测的无刷直流电机转子位置信号和采用霍尔传感器输出的位置信号完全一致,可与霍尔传感器所采用的成本低廉的转子位置译码芯片相配套.     

线反电动势检测无刷直流电机转子位置方法

利用传统的反电动势过零检测原理,提出一种利用简化的线反电动势过零检测无刷直流电机转子位置方法,该方法通过实时测量无刷直流电机的任意两路线电压和两路相电流信号,并利用定子电阻参数进行实时简化计算,就可以得到三路线反电动势的过零时刻,从而实现无刷直流电机的无位置传感器控制.该方法结构简单、计算方便,不需要构造电机中点,也不需要进行相位延迟补偿,定子电阻变化对转子位置辨识的精确度影响较小.仿真和实验结果表明,提出的改进线反电动势过零检测方法可以在较宽的速度范围内对转子位置进行准确检测.     

Model-based detection of rotor faults without rotor position sensor-the sensorless Vienna monitoring method

This paper deals with an extended approach of the Vienna Monitoring Method (VMM), which is a model-based technique to detect rotor asymmetries in the squirrel cage of an induction machine. The conventional VMM requires the measured voltages, currents, and the signal of a rotor position sensor. The novel scheme presented in this paper alternatively works without a rotor position sensor. In particular, for low-inertia drives, accurate estimation of rotor position is required. The rotor-fault-related double-slip-frequency torque modulation causes a speed ripple with the same frequency. Consequently, low-inertia drives are exposed to higher speed ripples. In this case, it is not sufficient to estimate the mean value of the actual speed, only. Even the speed ripple has to be acquired to benefit from the accuracy of the employed models of the VMM. The proposed technique evaluates the signatures of an inherent rotor fault in order to determine the rotor position signal. The speed ripple can be obtained from the torque modulations that the models already compute. This way, an accurate rotor fault detection technique without rotor position sensor can be realized.     

改进的面贴式永磁同步电机转子初始位置检测

针对基于常规的高频注入法在检测永磁同步电机(PMSM)转子初始位置时,存在位置估算结果可能反向的问题,根据定子铁心的非线性磁化特性,提出了一种转子永磁体N/S极极性判定和转子初始位置检测的方法.通过对高频电流负序分量的分析,提取转子凸极位置信息,并利用旋转电流矢量幅值变化的情况,完成转子永磁体N/S极极性判定,解决了常规高频注入法存在的问题,准确检测出转子的初始位置.通过对一台面贴式PMSM的转子初始位置检测实验,验证了该方法的有效性.     

Sensorless rotor position estimation of an interior permanent-magnet motor from initial states

This paper describes a torque, speed, or position control method at standstill and low speed in the interior permanent-magnet motor (IPMM) drive system without any rotational transducer. While IPMMs have originally magnetic saliency, it varies according to the load conditions and the control performance can be easily degraded. In this paper, the saliency or impedance difference is used as the conventional methods and, nevertheless, in order to amplify the difference containing the information of the rotor angle and to maintain a reasonable performance under any load condition a high-frequency injection scheme is proposed. A speed and position estimation scheme based on the characteristics of the high-frequency impedance is proposed. The scheme extracts the high-frequency impedance components related to the rotor position. An initial angle estimation scheme for starting from an arbitrary rotor position is also proposed. It can distinguish the north magnetic pole position from the south one in several decade milliseconds. The proposed scheme enables position control of a transducerless or position-sensorless IPMM. The experimental results clarify the satisfactory operation of the proposed position control algorithm under any load condition.     

Improved cage rotor models for vector controlled induction motors

Variations in motor model parameters lead to the detuning of vector controllers which, in turn, cause a deterioration in performance, particularly during transient and field weakening operation. Parameter adaptation schemes seek to change the model parameters based on observed performance, but are still based around a simple model for the machine which is not adequately representative. Improved motor models, based on deeper phenomenological understanding of the machine offer a viable alternative. In this paper, the authors present a model which enables rotor leakage and main flux path saturation and deep-bar effects to be taken into account. The model is verified experimentally using a 7.5-kW 4-pole motor, mounted on a piezoelectric force table which enables transient torques to be measured     

双极性分块转子开关磁阻电机

针对单极性励磁时四相8/6结构分块转子开关磁阻电机的定子磁通冲突问题,把双极性励磁方法应用于四相8/6结构分块转子开关磁阻电机,基于2D有限元建立双极性分块转子开关磁阻电机的场路耦合模型,计算双极性分块转子开关磁阻电机的电流、转矩及铜耗,并在(r,θ)坐标系中细致描述定子铁心和转子铁心特征区域的磁密周期性变化规律,最后应用双频法分离铁损获得铁心的涡流损耗和磁滞损耗.计算结果表明,与同等双极性励磁的8/6结构双极性普通开关磁阻电机相比,8/6结构双极性分块转子开关磁阻电机的转矩脉动大,但铜耗减小约32%,铁耗减小约35%.